Description : What are some disadvantages of operating transmitters at or near the luf?
Last Answer : Signal-to-noise ratio is low and the probability of multipath propagation is greater.
Description : When is muf at its highest and why?
Last Answer : Muf is highest around noon. Ultraviolet light waves from the sun are most intense.
Description : What do the letters muf, luf, and fot stand for?
Last Answer : Muf is maximum usable frequency. Luf is lowest usable frequency. Fot is commonly known as optimum working frequency.
Description : What are the transmitter operating modes?
Last Answer : Lsb, usb, isb, AM, cw, fsk.
Description : What is the highest frequency that can be sent straight upward and be returned to earth? A. MUF B. Gyro frequency C. Skip frequency D. Critical frequency
Last Answer : D. Critical frequency
Description : To obtain the most reliable sky wave propagation the ____ should be used. A. Lowest useable frequency (LUF). B. Maximum useable frequency (MUF). C. Optimum useable frequency (OUF). D. Critical frequency
Last Answer : C. Optimum useable frequency (OUF).
Description : At a certain time, the MUF for transmission at an angle of incidence of 75° is 17 MHz. What is the critical frequency? A. 4.4 MHz B. 3.5 MHz C. 6.5 MHz D. 1.5 MHz
Last Answer : A. 4.4 MHz
Description : What precaution should you take when substituting a synchro tester in a circuit for a transmitter?
Last Answer : Use only one receiver so as not to overload the tester.
Description : What is the most likely problem if the transmitter shaft reads 0º when the receiver shaft indicates 180º?
Last Answer : The rotor leads on either the transmitter or the receiver are reversed.
Description : What is the relationship between the transmitter and receiver stator voltages when their rotors are in correspondence?
Last Answer : The voltages are equal and oppose each other.
Description : What is the physical difference between a synchro transmitter and a synchro receiver?
Last Answer : A synchro receiver uses some form of damping to retard excessive oscillations or spinning.
Description : Describe the zero-position of a synchro transmitter.
Last Answer : The transmitter is in its zero-position when the rotor is aligned with the S2 stator winding.
Description : What unit of measurement refers to the torque of a synchro transmitter
Last Answer : Ounce-inches.
Description : What are three ways of controlling the amount of transmitter-generated emi?
Last Answer : (a) filtering and shielding of the transmitter (b) limiting bandwidth (c) cutting the antenna to the
Description : Transmitter power readings are most often referenced to what power level?
Last Answer : 1 milliwatt.
Description : Where should the transmitter spectrum be located with respect to the receiver response curve?
Last Answer : In the center.
Description : The spectrum of a radar transmitter describes what characteristic of the output pulse?
Last Answer : Frequency distribution
Description : Immediately after the transmitter fires, stc reduces the receiver gain to what level?
Last Answer : Zero.
Description : What type of klystron is used as the final stage of a power- amplifier transmitter?
Last Answer : Multicavity klystron.
Description : What controls transmitter pulse width?
Last Answer : The modulator.
Description : What transmitter component allows the radiation of a large number of discrete frequencies over a wide band?
Last Answer : . Frequency synthesizer.
Description : In an externally synchronized radar, what determines the prr of the transmitter?
Last Answer : The master oscillator.
Description : What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?
Last Answer : Pulse-Doppler.
Description : What factor determines the difference between the transmitted frequency and the received frequency in an fm transmitter?
Last Answer : Travel time.
Description : The beat frequency in a swept-frequency transmitter provides what contact information?
Last Answer : Range.
Description : When a transmitter uses a high-power oscillator to produce the output pulse, what switches the oscillator on and off?
Last Answer : High-voltage pulse from the modulator.
Description : What type of radar transmitter power is measured over a period of time?
Last Answer : Average power.
Description : What vswr is a perfect match between a transmitter and its load?
Last Answer : 1 to 1.
Description : What is the result of an impedance mismatch between a receiver or transmitter and its transmission line or antenna?
Last Answer : High vswr, which equates to poor reception or a loss of power output.
Description : All the power sent down a transmission line from a transmitter can be transferred to an antenna under what optimum conditions?
Last Answer : When the characteristic impedance of the transmission line and the load impedance are equal.
Description : What term is used for the end of the transmission line that is connected to a transmitter?
Last Answer : Input end, generator end, transmitter end, sending end, and source.
Description : What connecting link is used to transfer energy from a radio transmitter to its antenna located on
Last Answer : Transmission line.
Description : List five common fiber optic transmitter packages.
Last Answer : TO can, DIP, butterfly lead microcircuits, circuit cards, and stand-alone optical fiber converters.
Description : Which part of a fiber optic transmitter converts the processed electrical signal to an optical signal?
Last Answer : The optical source.
Description : What are the three parts of a fiber optic transmitter?
Last Answer : Interface circuit, source drive circuit, and an optical source.
Description : What is the range of earth terminal transmitter output power?
Last Answer : Up to 20 kilowatts.
Description : In an fm transmitter, when does an oscillator generate only a steady frequency?
Last Answer : When no modulation is present.
Description : What purpose does a microphone perform in an AM transmitter?
Last Answer : It converts audio (sound) into electrical energy.
Description : What is the final stage of a transmitter?
Last Answer : Power amplifier.
Description : What is the function of the oscillator in a cw transmitter?
Last Answer : It generates an rf carrier at a given frequency within required limits.
Description : What are the four basic transmitter types?
Last Answer : Am, fm, cw, ssb.
Description : A step transmitter is a modification of what electrical device?
Last Answer : Rotary switch.
Description : What capability does a transmitter transfer switchboard provide?
Last Answer : Transferring remote control functions and signals to transmitters.
Description : What are the two major sections of a typical AM transmitter?
Last Answer : Rf and af units.
Description : What is the purpose of frequency-multiplier stages in a VHF transmitter?
Last Answer : To raise the low frequency of a stable oscillator to the vhf range.
Last Answer : Antenna-to-ground capacitance can cause the oscillator frequency to vary.
Description : State the method used to increase the speed of keying in a cw transmitter.
Last Answer : Machine keying.
Description : For a shortened vertical antenna, where should a loading coil be placed to minimize losses and produce the most effective performance? A. As low as possible on the vertical radiator B. Near the center of the vertical radiator C. As close to the transmitter as possible D. At a voltage node
Last Answer : B. Near the center of the vertical radiator